AC/Heat only come out through the defrost

96 explroer XLT V8.....our ac/heat both blow out of the defrost....the AC is still ice cold and the heat blazing hot....now the main problem is that when u use the AC it causes the windshield to fog....i am at a loss...we need these swithches working again its to freakin hot.....plz help

First thing to check is

all the vacuum connections, starting with the plug near the passenger's right little toe. "Def" is the "default" position, when you have a total vacuum failure, by regulation.

umm english please...i don't understand that

It "ain't" the switches...

the little plastic hoses from the RH AC/HEAT/DEF switch, or more likely the little hoses on the very far right side of the firewall above the right front corner of the carpet, or the little supply hose in the engine compartment have been disconnected or broken.

Since the law only requires cars to have windshield defoggers, this is where the spring-loaded doors on the heater will send your air when the vacuum fails.

Check that small black, and white check valve that is inline with the vacuum line going to the A/C vacuum controls. Motormite's help section sells them. You could try to spray it out with a little WD-40, or brake cleaner first to see if that helps. It might just be a little clogged.

Here is the link to it on their website: 47149 check valve.
This is what it looks like:

where is the little supply hose located

Check under the hood. There are vacuum lines running off of the vacuum tree, or "octopus" connector as it is also referred to. Trace the line from there to that check valve. The other side of that check valve is going to your vacuum controls for the A/C vents.

sry guys u gotta be more descriptive...im not new to engines but this one is a mess of wires and is crammed in being that its a V8....around what parts is the "the vacuum tree, or "octopus"" located

It's located on the top rear of the intake manifold. That part has all of the vacuum lines running into it.

Here are some pictures from Glacier991's photo gallery:

OK, let's start with the easy ones...

Sit in the passenger seat. Above your left foot, hidden by the glove box, is the hose "gang plug" connecting the control to the heater. Make sure it is connected. Above your right foot, at the lower right corner of the heater, is a two-hose connector which attaches the heater to the vacuum supply in the engine compartment. I knocked this one loose once, and the air would only come out the defogger vent. Sound familiar?

If these are OK, get back to us.

yep i checked both of the ones in teh car and there fine...we had the passengers side exhast manifold replaced 3 years ago when we bought the car and it hasn't worked since then so im thinkin they either cut,broke, or melted a hose when they did it....btw is that a 6 or a 8 cylinder...it looks kidan different

Those pictures were from Glacier's photo gallery. I think he has a 6 cylinder. It might be a 4.0L. I have a 3.0L, and mine is different.

well i have no idea where the vacum tree is...

Just take a look at the top rear of the engine. You will see a bunch of vacuum hoses going into it.

I havent read every post but did anyone mention the blend door that always gets stuck? just a thought good luck ,Jon

Lets' do this vacuum hose the easy way...

over by the passengers' right foot was two hoses connected to the firewall. They come out in the engine compt under the blower motor. One goes directly to the hot water shutoff valve. The other one is the supply line that operates all the vacuum stuff under the dash. Follow it. It should go to a module under the air cleaner, then up to the intake near the throttle, etc.

ok i found it.....everythigns in tact over there but i have yet to crawl under the car...now if i unplug that plug that goes into teh firewall should i feel vacum pressure

Yes, if you unplug the two-hose connector under the dash at the firewall on the far right side while the engine is running, one of them should be sucking air. BTW, if this hose is cut or broken at some point, at some point, it is causing a vacuum leak, so your mileage and power should be very slightly improved when reconnected.